Wafer fabrication facilities are commonly organized to include areas in which chemical vapor deposition, plasma deposition, plasma etching, sputtering and the like are carried out. In order to carry out many of these processes, it is necessary that the tools which are used for the process, be they chemical vapor deposition reactors, vacuum sputtering machines, plasma etchers or plasma enhanced chemical vapor deposition, be supplied with various process gases which gases may be reactive or inert or provide reactive species. It may be appreciated that in each instance pure carrier gases or reactant gases must be supplied to the tool in contaminant-free, precisely metered quantities.
In a typical wafer fabrication facility the inert and reactant gases are stored in tanks which may be located in the basement of the facility and which are connected via piping or conduit to a valve manifold box. The tanks and the valve manifold box are considered to be part of the facility level system. At the tool level an overall tool system, such as a plasma etcher or the like, includes a gas panel and the tool itself. The gas panel contained in the tool includes a plurality of gas paths having connected therein manual valves, pneumatic valves, pressure regulators, pressure transducers, mass flow controllers, filters, purifiers and the like. All have the purpose of delivering precisely metered amounts of pure inert or reactant gas from the valve manifold box to the tool itself.
The gas panel is located in the cabinet with the tool and typically occupies a relatively large amount of space, as each of the active devices are plumbed into the gas panel, either through welding tubing to the devices or combinations of welds and connectors such as VCR connectors. Gas panels are relatively difficult to manufacture and hence expensive. In a combination VCR connector and welded tubing system the individual components are held on shimmed supports to provide alignment prior to connections at VCR fittings. Misalignment at a VCR fitting can result in leakage.
Additional problems with conventional gas panels relate to the fact that a combination VCR and welded system of the type currently used today typically requires a significant amount of space between each of the components so that during servicing the VCR connections can be accessed and opened. In addition, in order to remove an active component from a contemporary gas panel, many of the supports of the surrounding components must be loosened so that the components can be spread out to allow removal of the active component under consideration.
The advent of modular surface mount (“MSM”) fluidic components, beginning in the mid-nineteen nineties, is perceived as a significant milestone in reducing the size of fluidic systems. That is, systems comprised of fluid control and measurement components such as valves, regulators, filters, pressure transducers, mass flow meters, and mass flow controllers. Prior to MSM interfaces, such components were typically joined for fluid communication by interconnecting tubulations either via welding or via reusable gasketed connections. Either method was enabled by metal tubing protrusions, or appendages, intrinsic to each fluidic component for the express purposes of interconnection and fluid transport.
MSM interfaces did reduce the size, or “footprint,” of fluidic systems considerably. In MSM architecture, the fluidic component is sealed, typically with elastomer O-rings or metal gaskets, using bolts for compression, to a receptive MSM or “modular” architecture. Several MSM or modular architectures that are in common use are described in U.S. Pat. No. 5,836,355; U.S. Pat. No. 6,874,538; U.S. Pat. No. 6,951,226; U.S. Pat. No. 6,293,310 and U.S. Pat. No. 7,048,008. A common aspect of these disclosures is twofold: (1) to provide for the standardized fluidic interface to seal to the MSM component and (2) to provide interconnecting gas conduits for the purpose of routing fluids into, out of, and between fluidic components.
The reduction of size and internal “wetted” area and volume afforded by modular fluidic systems are well understood, especially within the semiconductor wafer processing industry wherein size, purity of fluids, cleanliness of the gas system, and serviceability are prized attributes of any fluidic system.
Although MSM-type fluidic systems offer advantages in terms of reduced size, reduced area and volume exposed to the controlled fluids, and improved serviceability, the MSM component typically must be sealed to a receptive modular architecture in the manner disclosed by the aforementioned patents. Put in another way, the MSM fluid component is typically mated to a corresponding modular interface in order to complete the fluidic circuit. Conventionally, this corresponding modular interface is provided by modular architectures of various designs but all of which embody the standard modular interface as set forth by SEMI Standards F86-0304 and F87-0304, among others.
While there exist a number of ways to assemble gas panel systems, I have devised a new approach that minimizes space requirements, substantially eliminates the number of parts needed and allows easy servicing of MSM components. My invention addresses the various difficulties associated with the use of prior art gas panel assemblies by using MSM components having U-shaped interconnections that interface and secure one or more modular fluid inserts to a base or support plate. The U-shaped design has alignment legs that straddle the modular fluid inserts in a pressing engagement against a planar support plate when the interconnection is fastened directly to a planar support surface. The fluid inserts have at least one alignment connector on its bottom side that removably engages alignment slots cut into the planar surface. These and other features of my invention are described below.